Toxicological and analytical investigations of noni (Morinda citrifolia) fruit juice   总被引：1，自引：0，他引：1  

Westendorf J  Effenberger K  Iznaguen H  Basar S 《Journal of agricultural and food chemistry》2007,55(2):529-537

Morinda citrifolia (noni) is known to contain genotoxic anthraquinones in the roots. Because of the widespread use of noni juice, the possible genotoxic risk was examined through a battery of short-term tests. Noni juice was also chemically analyzed for the possible presence of anthraquinones. Noni juice extract in the Salmonella microsome assay showed a slight mutagenic effect in strain TA1537, due to the presence of flavonoids. No mutagenicity was observed in the mammalian mutagenicity test with V79 Chinese hamster fibroblasts. Rats treated with a noni juice concentrate did not show DNA repair synthesis (UDS) in primary rat hepatocytes, nor could DNA adducts or DNA strand breaks be observed. HPLC analysis of noni juice for anthraquinones was negative, with a sensitivity of <1 ppm. In summary, chemical analysis and genotoxicity tests reveal that noni juice does not have a genotoxic potential and that genotoxic anthraquinones do not exist in noni juice.  相似文献   

Using LC-MSMS to assess glutathione levels in South African white grape juices and wines made with different levels of oxygen     

du Toit WJ  Lisjak K  Stander M  Prevoo D 《Journal of agricultural and food chemistry》2007,55(8):2765-2769

The effect of oxygen on the levels of glutathione, an important antioxidant, in must and wine was studied using a novel LC-MSMS method for the analysis of reduced and oxidized glutathione. This study found that the storage of grape juice at high SO2 and ascorbic acid levels at -20 degrees C did not lead to a decrease in reduced glutathione levels. The effect of varying the oxygen levels in South African white grape juices, which included a reductive treatment (less than 0.3 mg/L dissolved O2 added), a control treatment (between 1.0 and 1.5 mg/L dissolved O2 added), and an oxidative treatment (3.5-4 mg/ L dissolved O2 added, without SO2) on reduced glutathione levels in the juice and resulting wine was also investigated. A custom build press was used to press whole bunches of two different Sauvignon Blanc and Colombard grapes. Alcoholic fermentation and oxygen additions to the must led to lower reduced glutathione levels in the wine. Reduced glutathione levels were only significantly higher in the wine made from reductive juice that had the highest initial reduced glutathione levels in the grapes.  相似文献   

Ethnic differences in 1-year follow-up effect of the Dutch Schoolgruiten Project - promoting fruit and vegetable consumption among primary-school children     

Tak NI  Te Velde SJ  Brug J 《Public health nutrition》2007,10(12):1497-1507

OBJECTIVE: To evaluate the effect of a primary school-based intervention providing free fruit and vegetables (F&V), separately for children of Dutch and of non-Western ethnicity. SETTING: Primary schools in two regions (west and east) in The Netherlands. DESIGN AND METHODS: Participating schoolchildren and their parents completed questionnaires at baseline and 1 year later, including questions on usual F&V intake, potential determinants and general demographics. Primary outcomes were the usual fruit intake and the usual vegetable intake as assessed by parent- and child self-reported food frequency measures. Secondary outcome measures were child- or parent-reported taste preference, knowledge of daily recommendations, availability, and accessibility for fruit intake. Multilevel regression analyses were used to assess differences at follow-up adjusted for baseline values between the control and intervention group using both child and parent reports. SUBJECTS: Five hundred and sixty-five children of Dutch ethnicity and 388 children of non-Western ethnicity (mean age 9.9 years at baseline) and their parents. RESULTS: Children of non-Western ethnicity in the intervention group reported a significantly higher vegetable intake (difference = 20.7 g day-1, 95% confidence interval (CI) = 7.6-33.7). A significant positive intervention effect was also found for fruit intake for children of Dutch ethnicity (difference = 0.23 pieces day-1, 95% CI = 0.07-0.39). No significant effects in intake were observed based on parent reports. Significant positive intervention effects were also found for perceived accessibility among children of non-Western ethnicity, as well as for parent-reported taste preference of their child among children of non-Western ethnicity and boys of Dutch ethnicity.CONCLUSION: Providing children with free F&V had some positive effects on child-reported intakes and important correlates of intakes.  相似文献   

The effects of a middle-school healthy eating intervention on adolescents' fat and fruit intake and soft drinks consumption     

Haerens L  De Bourdeaudhuij I  Maes L  Vereecken C  Brug J  Deforche B 《Public health nutrition》2007,10(5):443-449

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Exploiting trap color to improve surveys of longhorn beetles     

Cavaletto  Giacomo  Faccoli  Massimo  Marini  Lorenzo  Spaethe  Johannes  Giannone  Filippo  Moino  Simone  Rassati  Davide 《Journal of pest science》2021,94(3):871-883

Journal of Pest Science - Longhorn beetles are commonly moved among continents within wood packaging materials used in trades. Visual inspections carried out at points of entry often fail to detect...  相似文献   

Influence of storage conditions on viability of quiescent copepod eggs (Acartia tonsa Dana): effects of temperature, salinity and anoxia     

Martin Holmstrup  Johannes Overgaard  Thomas F. Sørensen  Guillaume Drillet  Benni W. Hansen  Hans Ramløv  & Kirsten Engell-Sørensen 《Aquaculture Research》2006,37(6):625-631

Copepods have proven to be an ideal source of live food for the production of marine fish larvae in aquaculture. Therefore, there is a need to develop new methods for production and storage of copepod eggs that can be hatched and used at fish farms. In the present study quiescent eggs of Acartia tonsa were stored for periods up to 35 weeks at different temperatures, salinities and oxygen conditions in a full factorial experiment. None of these storage conditions seemed to induce diapause in eggs even though this has been reported by other authors. The most promising storage conditions were those involving low temperature (<5°C), medium salinity (10–20 ppt) and anoxia. The practical aspects of these results for aquaculture are discussed.  相似文献   

Interacting effects of diet and environmental temperature on biochemical parameters in the liver ofLeuciscus idus melanotus (Cyprinidae: Teleostei)     

Johannes Rafael  Thomas Braunbeck 《Fish physiology and biochemistry》1988,5(1):9-19

One year old golden ide (Leuciscus idus melanotus) were starved for 2 weeks at 20°C (time zero) and then they were fed either freeze-dried mosquito larvae (natural diet) or a commercial fish chow (artificial diet) at an ambient temperature of 14°C and 20°C, respectively. Growth parameters and biochemical data in the liver were measured at time zero and after 3 and 7 weeks of specific regimen. If compared to natural food, the artificial diet caused transient increase in anabolic activity of the liver, but prevented long-lasting hepatocyte proliferation (increase of total liver DNA). After 3 weeks on artificial diet, the body weight was significantly higher and the liver mass doubled compared to ide kept on the natural regimen; tissue DNA content indicated that the hepatocyte volume increased mainly by increased protein content and corresponding uptake of water; lipid and glycogen contents were increased by a factor of 3–6, and the RNADNA ratio was increased accordingly. The growth of the ide, as reflected by the condition factor and hepatosomatic index (HSI), was virtually stopped when the artificial regimen was maintained for 7 weeks, whereas on natural food the condition factor was increased and liver weight and DNA were doubled. Growth of the fish maintained at 14°C was significantly lower than that of fish maintained at 20°C, though the total liver DNA was still increased on the natural regimen during the experiment. Less lipid was stored by fish maintained at 14°C, whereas protein and glycogen deposits were enlarged, if compared to fish maintained at 20°C. The specific activity of cytochrome oxidase in liver mitochondria and of NADPH cytochrome c reductase in the microsomal fraction were found independent of diet and ambient temperature. Oxidative capacity of hepatocytes (mitochondrial protein/mg DNA) remained unchanged, and microsomal protein/cell appeared reduced in response to the artificial food. However, reduction of cell number on this diet resulted in less total mitochondrial and microsomal protein in the organ. Golden ide liver is found to be a sensitive experimental model to characterize the mutual influence of diet and temperature on fish; the results are discussed with regard to the usage of golden ide as test fish for water pollution.  相似文献   

Investigating the mechanisms for the opposing pH relationships of fungal and bacterial growth in soil     

Johannes Rousk  Philip C. Brookes 《Soil biology & biochemistry》2010,42(6):926-934

Soil pH is one of the most influential variables in soil, and is a powerful factor in influencing the size, activity and community structure of the soil microbial community. It was previously shown in a century old artificial pH gradient in an arable soil (pH 4.0-8.3) that bacterial growth is positively related to pH, while fungal growth increases with decreasing pH. In an attempt to elucidate some of the mechanisms for this, plant material that especially promotes fungal growth (straw) or bacterial growth (alfalfa) was added to soil samples of the pH gradient in 5-day laboratory incubation experiments. Also, bacterial growth was specifically inhibited by applying a selective bacterial growth inhibitor (bronopol) along the entire pH gradient to investigate if competitive interaction caused the shift in the decomposer community along the gradient. Straw benefited fungal growth relatively more than bacterial, and vice versa for alfalfa. The general pattern of a shift in fungal:bacterial growth with pH was, however, unaffected by substrate additions, indicating that lack of a suitable substrate was not the cause of the pH effect on the microbial community. In response to the bacterial growth inhibition by bronopol, there was stimulation of fungal growth up to pH 7, but not beyond, both for alfalfa and straw addition. However, the accumulation of ergosterol (an indicator of fungal biomass) during the incubation period after adding alfalfa increased at all pHs, indicating that fungal growth had been high at some time during the 5-day incubation following joint addition of alfalfa and bronopol. This was corroborated in a time-series experiment. In conclusion, the low fungal growth at high pH in an arable soil was caused to a large extent by bacterial competition, and not substrate limitation.  相似文献   

Loss of low molecular weight dissolved organic carbon (DOC) and nitrogen (DON) in H₂O and 0.5 M K₂SO₄ soil extracts     

Johannes Rousk  Davey L. Jones 《Soil biology & biochemistry》2010,42(12):2331-2335

Soil extracts are routinely used to quantify dissolved organic nutrient concentrations in soil. Here we studied the loss and transformation of low molecular weight (LMW) components of DOC (¹⁴C-glucose, 1 and 100 μM) and DON (¹⁴C-amino acid mixture, 1 and 100 μM) during extraction of soil (0-6 h) with either distilled water or 0.5 M K₂SO₄. The extractions were performed at 20 °C, at 4 °C, or in the presence of an inhibitor of microbial activity (HgCl₂ and Na-azide). We showed that both glucose and amino acids became progressively lost from solution with increasing shaking time. The greatest loss was observed in H₂O extracts at 1 μM for both substances (>90% loss after 15 min). Lower temperature (4 °C) and presence of K₂SO₄ both resulted in reduced loss rates. The presence of microbial inhibitors effectively eliminated the loss of glucose and amino acids. We conclude that microbial transformation of LMW-DOC and DON during H₂O or K₂SO₄ extraction of soil may affect the estimation of their concentrations in soil. This finding has significant implications for methods that rely on chemical extractions to estimate LMW-C components of DOC and DON.  相似文献   

Korrelationen zwischen den Werten der Saugkraft,der Zellsaftkonzentration und des Feuchtegehaltes in Zuckerrübenblättern und die Abhängigkeit der Zellsaftkonzentration von der Luft- und Bodenfeuchtigkeit     

Johannes Birke 《Archives of Agronomy and Soil Science》2013,59(12):1041-1049

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